Njalla is a privacy-aware domain service. It provides DDNS functionality, which can be found here. Could anybody help me with this support? I have programming experiences but not quite familiar with OpenWrt pkg structure. Thanks.
I think you need to describe what you want to do with it. You can just use tools like
wget to make REST calls to this API. You can use cronjobs or write your own shell scripts with procd support, to interact with this API.
Have a look at this guide, it pretty much explains all you need to do to configure it: https://openwrt.org/docs/guide-user/services/ddns/client
The programming part is pretty straightforward. What I am not sure about are the opkg package system and the repository. I saw some commit not only on the script itself, but also a whole bunch of changes on the tracking files.
I am not sure why you think need to get involved with the packages... You just need to install "luci-app-ddns" and "ddns-scripts", then configure it according to your needs. Or are you trying to do anything else?
The official package does not support njalla, which I'm considering contribute code to the package.